@dmykins this is the 6” model, a
I don’t know if you want to upgrade to a larger model, but this company makes up to a 12” I think. The 8” isn’t much more than the 6”.
I have this one. You can order it without a controller, but I recommend one with. You can add another fan to this single controller for a dual fan set up, fans sync with each other, or an additional tent. Sky is the limit.
AC Infinity CLOUDLINE T6, Quiet 6" Inline Duct Fan with Temperature Humidity Controller - Ventilation Exhaust Fan for Heating Cooling Booster, Grow Tents, Hydroponics
https://www.amazon.com/dp/B074XBXFPD/ref=cm_sw_r_cp_api_i_WxtgEb2654K6M